Re: memory usage of code compiled with gcc 3.2

[Andrea 'Fyre Wyzard' Bocci <fwyzard at inwind dot it>]

At 10.54 27/12/2002 -0300, hektor monteiro x285 wrote:

> Hi everyone! I am working with an astrophysical code that uses a lot of 
> memory (RAM). Basically because of a 3D matrix that I have to define. I 
> was working with 1G  of RAM before and could run the code with a cube of 
> 70^3 cells. Recently I bought a new super machine with 4g of RAM and I am 
> using the gcc 3.2 compiler on linux redhat 7.3. But I am not able to run 
> more than 70^3 cells on this. Can anyone give me some clue?? I would think 
> I should be able to do better no? Is this a linux kernel limitation or gcc 
> or something else??
>
> cheers,
>
> Hektor
Hi Hector.
Actually, there are limitations on the size arrays con have with GCC, but I 
don't think you've stumbled in that. A 70*70*70 array is 343000 cells; 
using doubles, that'd amount to little over 2.6 MB. I think up to arrays of 
500*500*500 doubles you should have no problem (apart from exausting RAM, 
that is :-).

So, could you be a little more specific on what "I am not able to run more 
than 70^3 cells" means ? Do you get errors at compile time, or run time ? 
And, especially at runtimewhat kind of errors ?

fwyzard